Liquefied gas storage and dispensing system



Sept. 14, 1948. l.. J. wHlTE LIQUEFIED GAS STORAGE AND DISPBNSING SYSTEI Filed Nov. 27, 1945 nllililllu Patented Sept'. y14, 1948 LIQUEFIED GAS STORAGE AND DISPEN SIN Gl SYSTEM Loyd J. White, San Antonio,

Tex., assigner to Southern Steel Company, San Antonio, Tex., a corporation of Texas I Application November 27, 1945, Serial No. 631,132 2 Claims. (Cl. {i2-1) This invention relates to a liquefied gas stori age and dispensing system for delivering gas of a substantially uniform B. t. u. content from a` mixture oi liquehed petroleum gas, such as commercial butane and propane. Among other objects, the invention aims to provide a greatly improved'two-stage liquid eduction system having a first; stage pressure reducing regulator and a vaporizer submerged within the stored liquid in a pressure storage container, the idea .being to prevent the valve of the regulator from sticking, due to freezing, and to insure complete vaporization of the liquid passing through the first stage regula-tor to the second stage regulator.

Another aim of the invention is to provide a two-stage system in which the i'lrst stage pressure reducing regulator, together Iwith the associated vaporizer, may be inserted in and removed from the pressure storage container, the construction and arrangement being such that the appurtenances can be factory-assembled. The main idea is to provide an improved system of this type contrived to supplant the type of system shown in my co-pending application, Ser. No. 237,113, filed October 26, 1938.

Other aims and advantages of the invention l will appear inthe specication, when considered in connection with the wherein:

Fig. 1 is a side elevation, partly in section, showing an underground, two-stage system embodying the invention; and

Fig. 2 is a Afragmentary sectional View, on an enlarged scale, showing a portion of the valved itting shown in Fig. 1.

Referring particularly to the drawing, the illustrated system is shown as being of the underground type, although it is to be understood that the improvements may be applied to abovegroundsystems. In two-stage systems of this general type, wherein the first stage pressure reducing regulator is located-outside the tank, the rapid cooling effect caused by flash vaporization of some of the liquid passing through the accompanying drawings,

y regulator has caused the contained moisture in the liquid to freeze and make the regulator valve stick so that it would not function properly. That is one of the main objections to a system `of the type shown in the aforesaid rcio-pending application. Moreover, when a vaporizer for the residual liquid which passes through the rst stage regulator, is arranged in the 'tank or storage container, it has heretofore -been necessary to install it during the fabrication of the tank.I

generating and which may -be of the This invention provides a combined first stage regulator and vaporizer which can be inserted in the tank after it tactory-assembled.

In-the present example, there is shown an ordinary, underground pressure storage tank lll adapted to be -.burned below the frost line to absorb vaporizing heat from earth. It is supplied with liquefied petroleum gas, such as a mixture of butane and propane. A short section of large conduit II is shown as being welded to the tank and 1t has a flange l2 to which the dispensing appurtenances are adapted to -be connected. A standpipe I3, having a flange I4, isV conveniently. bolted tothe flange I2 and carries a combination fitting I5, general type shown in my U. S. Patent 2,176,829. The iitting is shown as having a filler valve I6, a vapor return valve l1 and a level gauge I8 of the naat-operated type. However, it is understood that a slip tube gauge may be employed.

In this instance, the anged connection between the standpipe I3 and the short conduit II is shown as carrying a metal casing IS having a vented cover 20 above the ground level to provide a protective housing for the appurtenances.

In accordance with this invention, a ilrst stage pressure reducing regulator 2| of the usual diaphragm type is shown as being submerged in the liquid in the tank and has a liquid inlet 242 near the bottom of the tank. The l,outlet 23 of the regulator is connected to a T fitting 24 and a vapor pipe 25 leads from one branch of the T fitting upwardly through t-he standpipe and is connected to the valved tting l5 to deliver gas through an outlet nipple 26 extending downwardly from the fitting.` The lead carries the usual cut-oli valve 2l in the passage leading to the nipple. To the other -branch of the T fitting there is connected a vaporizer in the form of a pipe coil or loop 28, the pipe being preferably Vmade of copper or other flexible material so that lt can be inserted through the large conduit section IlI and the arrangement is such that the vaporizing coil lies on the bottom of the tank I 0. The other end of the loop is shown as extending vertically through the standpipe and is connected to the fitting |15, as shown in Fig.

i 2, to provide means for 'blowing oi any residual heavy ends which may be collected in the coil 28. For that purpose, the iltting is shown as having a blow-01T passage 29 terminating in a screw threaded coupling y30, to which a blow-oil is fabricated and can be the surrounding f hose can be connected. The passage is shown as having a cut-off valve 3|.

The arrangement of the vaporizer coil or loop and the vapor tube is such that residual liquid will flow downwardly into the loop, while flashed vapor passes upwardly through the pipe 25. Then, the residual liquid is vaporized -by heat exchange with the liquid in the tank and rises in the coll to join the vapor passing through the pipe y2li.

It will be understood that the rst stage pressure reducing regulator is set to reduce the pres. sure to, say, about five or ten pounds. This adjustment can easily be made before the regulator is inserted in the container and does not require any change, as long as the regulator is functioning properly. However, it is necessary that the usual diaphragm regulator be vented to the atmosphere. To this end, a vent or breather pipe 32 is shown as being connected to the regulator and extends upwardly through the standpipe, being connected at its upper end to the iitting I5 and communicating with an outlet passage 33, shown in Fig. 2. The outlet opening,r is shown as having a screen 34 to prevent dust or dirt from being sucked into the breather pipe during the operation of the regulator. f

The generated vapor passes through the outlet 26 of the fitting I5 through an ordinary second stage pressure reducing regulator 35, shown as being supported on the side of the standpipe within the casing I9. It is set to reduce the pressure to about six ounces, or the required service pressure. The gas is delivered from the second stage regulator to an ordinary service pipe 36, shown as passing. downwardly through the bottom of the casing I3 and outwardly adjacent to the top of the tank.

Fromv the foregoing description, it will be understood that the system is designed to deliver vapor at a substantially uniform B. t. u. content from mixtures of butane and propane having diii'erent boiling points. Trouble, due to freezing and sticking valves is eliminated. Furthermore, the first stage regulator and the vaporizer can easily be inserted in and removed from the container, The vaporizing coil or loop can be periodically drained of any heavy ends which may accumulate therein, by operating the hand valve- 3I and blowing out the contents of the coil, due to the vapor pressure therein. This may be done by a service attendant when the tank is relled.

Obviously,` the invention is not restricted to the particular embodimentthereof herein shown and described; but the apparatus is capable of various modifications within the scope of the appended claims.

What is claimed is:

1. In a liquefied petroleum gas dispensing system for delivering gas of substantially uniform B. t. u. content from a mixture of liquefied petroleum gases, a. pressure storage container adapted to be charged with the liquid; a large conduit duit carrying a valved dispensing fitting; a fuel delivering conduit connected to the fitting and extending downwardly through the standpipe and` conduit into the bottom portion of the container a first stage pressure reducing regulator havin its outlet connected to the fuel delivering conduit and disposed in the bottom portion of the container and arranged to be submerged in the liquid fuel to absorb heat therefrom; and a vaporizing coil made of flexible pipe connected to the fuel lin the bottom portion of the container so that residual liquid will drain therein from the fuel delivering conduit and the regulator, the first stage pressure reducing regulator being of such size and so arranged in relation to the size of opening through the largel conduit connected to the upper portion of the container that the assembly may be -'removed from the container through said large conduit.

2. Apparatus, as set forth in claim l, whereinf` 'the vaporizer provides a reservoir at its lowest REFERENCES CITED The following references are of record in the file of this patent:I

UNITED STATES PATENTS Name Date Number l, f

Norway May 21,1946 

